Tetrakisazo dyes containing a stilbenylene or 2,2&#39;-disulfostilbenylene radical

ABSTRACT

Disclosed are compounds of the formula, ##STR1## wherein the X&#39;s are the same and are hydrogen or --SO 3  M, 
     Y is hydrogen, C 1-4  alkyl, C 1-4  alkoxy, hydroxy, halogen, --COOM or --SO 3  M, 
     K 1  and K 2  are the same or different and are both radicals of a coupling component, 
     either A 1  is --SO 3  M and one of B 1  and C 1  is --SO 3  M, the other being hydrogen, 
     or A 1  and C 1  are both hydrogen and B 1  is --SO 3  M, and 
     M is hydrogen or a non-chromophoric cation, their production and use in dyeing anionic dyeable substrates, for example, natural and regenerated cellulose, natural and synthetic polyamides, polyurethanes, polypropylene modified to contain basic groups, anodized aluminum, paper and, particularly, leather.

This application is a division of application Ser. No. 885,627, filed Mar. 13, 1978 and now U.S. Pat. No. 4,169,832, which in turn is a continuation-in-part of application Ser. No. 717,522, filed Aug. 25, 1976 and now abandoned.

The invention provides compounds of formula I, ##STR2## wherein the X's are the same and are hydrogen or --SO₃ M,

Y is hydrogen, C₁₋₄ alkyl, C₁₋₄ alkoxy, hydroxy, halogen, --COOM or --SO₃ M,

K₁ and K₂ are the same or different and are both radicals of a coupling component,

either A₁ is --SO₃ M and one of B₁ and C₁ is --SO₃ M, the other being hydrogen,

or A₁ and C₁ are both hydrogen and B₁ is --SO₃ M, and

M is hydrogen or a non-chromophoric cation.

The X's are preferably --SO₃ M groups. Any halogen as Y is chlorine, bromine or fluorine, chlorine being preferred. Any alkyl or alkoxy as Y is preferably of 1 or 2 carbon atoms, methyl and methoxy being especially preferred. Y is preferably hydrogen, chlorine or --SO₃ M, any chlorine or --SO₃ M preferably being in meta-position to the azo-K₂ linkage. In the preferred compounds of formula I, A₁ is --SO₃ M and, of B₁ and C₁, C₁ is preferably --SO₃ M.

Where M is a non-chromophoric cation, the exact nature thereof is not critical and it may, for example, be any cation conventional in the anionic dyestuff art. As examples may be given the alkali metal, alkaline earth metal and optionally substituted ammonium cations, the preferred of which latter cations can conveniently be represented by the formula .sup.⊕ N(R)₄, wherein each R, independently, is hydrogen, C₁₋₃ alkyl or C₂₋₃ hydroxyalkyl, with the provisos that (i) where one or more R is hydroxyalkyl, at least one is hydrogen, and (ii) in any hydroxyalkyl, the hydroxy group is other than on the carbon-atom attached to the nitrogen. As specific examples of cations may be given the triethylammonium, tri- and tetra-methylammonium, mono-, di- and tri-ethanol- and -isopropanolammonium, unsubstituted ammonium, potassium, lithium and sodium cations. From the production standpoint, alkali metal, especially sodium, cations are preferred.

The radicals K₁ and K₂ are conveniently derived from any coupling component conventional in the anionic dyestuff art, especially from those conventionally employed as terminal coupling components in polyazo anionic dyes. They are preferably free from azo linkages. The preferred coupling components from which the radicals K₁ and K₂ are derived are K₁ '-H and K₂ '-H, i.e. those of formulae (a) to (e), ##STR3## wherein R₁ is hydroxy or a primary, secondary or tertiary amino group conventional in coupling component radicals, preferably --OH, --NH₂, mono- or di-C₁₋₄ alkylamino, mono- or di-C₂₋₄ hydroxyalkylamino, monosulphomethylamino, monoarylamino, N-C₁₋₄.spsb.- alkyl-N-C₂₋₄ hydroxyalkylamino, N-C₁₋₄ alkyl-N-arylamino or N-C₂₋₄ hydroxyalkyl-N-arylamino, any aryl being naphthyl, unsubstituted or mono- or di-substituted by--SO₃ M, or phenyl, unsubstituted or substituted by up to 3 substituents selected from C₁₋₄ alkyl (max.3), C₁₋₄ alkoxy(max.2), nitro(max.2), chlorine(max.2), --COOM(max.1) and --SO₃ M(max.1),

R₂ is hydrogen, hydroxy, --NH₂, C₁₋₄ alkyl, C₁₋₄.spsb.- alkoxy, chlorine or acylamino, where acyl is any conventional acyl group in coupling component radicals, preferably phenylsulphonyl, tolylsulphonyl, phenylcarbonyl, C₁₋₄.spsb.- alkylcarbonyl methylcarbonylmethylcarbonyl(acetoacetyl),

R₃ is hydrogen, C₁₋₄ alkyl, --SO₃ M or --COOM,

R₄ is --OH, --NH₂ or phenylamino, the phenyl being unsubstituted or substituted by C₁₋₄.spsb.- alkyl and/or C₁₋₄ alkoxy groups, preferably by up to 3 substituents selected from C₁₋₄.spsb.- alkyl(max.3) and C₁₋₄ alkoxy(max.2),

R₅ is hydrogen, --OH, --NH₂, --NHCH₂ SO₃ M or acylamino, acyl being as above defined,

m is 1, 2 or 3,

R₆ is hydrogen, C₁₋₄ alkoxy or --COOM, being --COOM only when m is 1,

R₇ is acyl, as defined above,

R₈ is naphthyl, unsubstituted or mono- or disubstituted by --SO₃ M, or phenyl, unsubstituted or substituted preferably by up to three substituents selected from C₁₋₄ alkyl(max.3), C₁₋₄ alkoxy(max.2), chlorine(max.2), methylcarbonyl(max.1) and --SO₃ M(max.1),

R₉ is hydrogen or phenyl, unsubstituted or monosubstituted by --SO₃ M,

R₁₀ is C₁₋₄ alkyl or --COOM, and

R₁₁ is --OH or --NH₂,

and those coupling components designated (fg), being the product of condensation, under acid conditions, of a compound or mixture of compounds of formula (f), ##STR4## and/or a compound or mixture of compounds of formula (g), ##STR5## R₁₃ to R₁₆, independently, being hydrogen, halogen, hydroxy or optionally substituted alkyl or alkoxy, and

M is as defined above,

with formaldehyde, the mol ratio of formaldehyde to the other compound(s) being at least 0.5:1, and at least 50 mol % of the other compound(s) containing a --COOM group.

In any C₁₋₄ alkyl substituted amino group as R₁, the alkyl group is preferably of 1 or 2 carbon atoms and in any C₂₋₄ hydroxyalkyl substituted amino group, the hydroxy group is on other than the α-carbon atom, preferably being on the β-carbon atom, the preferred C₂₋₄ hydroxyalkyl groups being C₂₋₃ hydroxyalkyl, especially β-hydroxyethyl. The preferred aryls in the aryl substituted amino group as R₁ are the unsubstituted and substituted phenyl radicals, in which any alkyl or alkoxy substituent is preferably methyl or methoxy, especially preferred arylamino groups as R₁ being of formula (ax), ##STR6## wherein Rx is hydrogen, --NO₂ or methyl,

Ry is hydrogen, --NO₂ or --SO₃ M, and

Rz is hydrogen, --COOM or methyl,

where two or more substituents selected from --NO₂, --COOM and --SO₃ M are present, such preferably being in metapositions relative to each other, particularly preferred arylaminos as R₁ being ortho-tolylamino, phenylamino, 2-nitro-4-sulphophenylamino and 2-sulpho-4-nitrophenylamino.

The acyl as R₇ or in any acylamino as R₂ is preferably C₁₋₄ alkylcarbonyl, more preferably methylcarbonyl.

The phenyl, in any phenylamino as R₄, is preferably unsubstituted or mono- or di-, preferably mono-, substituted by methyl or methoxy.

Any C₁₋₄ alkyl or C₁₋₄ alkoxy on any phenyl as R₈ is preferably methyl or methoxy, respectively, the preferred phenyl significance of R₈ being unsubstituted phenyl and tolyl.

R₁ is preferably R₂₁, i.e. --OH, --NH₂, --N(CH₃)₂, --N(C₂ H₅)₂, --N(C₂ H₄ OH)₂, --NHCH₂ SO₃ M or monophenylamino (anilino), the phenyl group being unsubstituted or substituted by up to 3 substituents selected from methyl(max.3), methoxy(max.2), nitro(max.2), chlorine(max.2), --COOM(max.1) and --SO₃ M(max.1), the preferred phenylamino being of formula (ax) above. More preferably, R₁ is R₃₁, i.e. --OH, --NH₂, ortho-tolylamino, phenylamino, 2-nitro-4-sulphophenylamino, 2-sulpho-4-nitrophenylamino, --N(C₂ H₄ OH)₂ or --N(C₂ H₅)₂.

R₁ and R₂ are preferably ortho or meta to each other and when both are --OH, especially meta.

When R₂ is meta to R₁, it is preferably R₂₂, i.e. hydrogen, --OH, C₁₋₄ (preferably C₁ or 2)alkyl, --NH₂ or --NHCOCH₃, more preferably R₃₂, i.e. hydrogen, methyl, ethyl, --NH₂ or --NHCOCH₃.

When R₂ is in ortho position to R₁,R₁ is preferably R₂₁, as given above, more preferably R₄₁, i.e. --OH, --NH₂, --NHCH₂ SO₃ M or --N(C₂ H₅)₂, and R₂ is preferably R₂₀, i.e. hydrogen, C₁₋₄ alkyl, C₁₋₄ alkoxy, chlorine or acetylamino, more preferably R₃₀, i.e. hydrogen, methyl, methoxy or acetylamino, preferably up to a maximum of one of R₂₀ and R₃₀ or of R₂₁ and R₄₁ containing a nitrogen atom.

R₃, when R₁ and R₂ are meta one to the other, is preferably para to R₁ and is preferably R₂₃, i.e. hydrogen, C₁₋₄ alkyl or --SO₃ M, more preferably R₃₃, i.e. hydrogen, methyl or --SO₃ M, but --SO₃ M only when R₁ and R₂ are both --NH₂.

R₃, when R₁ and R₂ are ortho one to the other and R₁ is hydroxy, is preferably R₄₃, i.e. C₁₋₄ alkyl (preferably methyl) or --COOM, the latter group being ortho to the hydroxy group as R₁.

R₃, when R₁ and R₂ are ortho one to the other and R₁ is an amino group, is preferably hydrogen.

When R₂ is hydrogen, R₃ is preferably other than hydrogen and, in the case when R₂ is hydrogen, R₁ is preferably hydroxy, R₃ being ortho thereto.

R₄ is preferably R₂₄, i.e. hydroxy, --NH₂ and, when R₅ is hydrogen or hydroxy, additionally phenylamino, the phenyl being unsubstituted or substituted by up to two substituents selected from methyl and methoxy, preferably being unsubstituted or monosubstituted by methyl or methoxy, and more preferably being unsubstituted.

R₅ is preferably R₂₅, i.e. hydrogen, hydroxy, --NH₂ and, when R₄ is hydroxy, additionally tolysulfonylamino, benzamido, C₁₋₄ alkylcarbonylamino, preferably methylcarbonylamino (acetamido) or --NHCH₂ SO₃ M.

Preferably at least one of R₅ and R₆ is hydrogen.

When formula (b) contains two --SO₃ M groups they are preferably, not in ortho relative positions.

Preferably, R₆ is C₁₋₄ alkoxy (of which methoxy is preferred) only when R₅ is hydrogen and m is 2.

Preferably, R₆ is R₂₆, i.e. hydrogen, methoxy or --COOM, being methoxy only when R₅ is hydrogen and m is 2 and being --COOM only when R₅ is hydrogen and m is 1. Most preferably R₆ is hydrogen.

R₇ is preferably R₂₇, i.e. C₁₋₄ alkylcarbonyl, more preferably methylcarbonyl.

R₈ is preferably R₂₈, i.e. phenyl, unsubstituted or substituted by up to 3 substituents selected from C₁₋₄ alkyl (preferably methyl) (max.3), C₁₋₄ alkoxy (preferably methoxy) (max.2), chlorine (max.2), methylcarbonyl (max.1) and --SO₃ M (max.1), more preferably R₃₈, i.e. methylphenyl or unsubstituted phenyl, of which the latter is especially preferred.

R₉ is preferably R₂₉, i.e. phenyl or monosulphophenyl.

R₁₀ is preferably R₂₁₀, i.e. methyl or --COOM, more preferably methyl.

R₁₁ is preferably hydroxy.

Preferred compounds of formula (a) are those of formulae (a₁) and (a₂) ##STR7## particularly (a₁₁) and (a₁₂) ##STR8## more particularly (a₂₁) and (a₂₂) ##STR9##

Preferred compounds of formula (b) are those of formula (b₁), particularly (b₂) and more particularly (b₃), ##STR10##

Preferred compounds of formula (c) are those of the formula (c₁), particularly (c₂) and more particularly (c₃) ##STR11##

Preferred compounds of formula (d) are those of formula (d₁), particularly (d₂) and more particularly (d₃) ##STR12##

As regards the coupling component (fg), in the compounds of formulae (f) and (g), any alkyl or alkoxy radical is preferably of 1 to 4 carbon atoms, more preferably of 1 or 2 carbon atoms, except as stated below. As examples of substituents thereon may be given halogen, --COOM, cyano, hydroxy, C₁₋₄ alkoxy and hydroxy-C₁₋₄ alkoxy. Any alkoxy substituted by one of the last three mentioned substituents is preferably of at least 2 carbon atoms. Any halogen in the compounds of formulae (f) and (g) is preferably chlorine, but may also be fluorine, bromine or iodine.

The preferred significances of R₁₃, R₁₄ and R₁₆ are hydrogen, methyl, methoxy, hydroxy and chlorine, such, together with --O--CH₂ --COOM, being the preferred significances of R₁₅. At least one of R₁₃ and R₁₄ is preferably, hydrogen. Most preferably R₁₃, R₁₄ and R₁₅ are hydrogen. Most preferably, R₁₆ is methyl or a hydroxy group in meta-position to the hydroxy shown in formula (g).

As examples of compounds of formula (f) may be given salicylic, m-cresotic, 2,4- and 2,6-dihydroxybenzoic and 4-chloro-2-hydroxybenzoic acids and salts thereof, salicylic acid and salts thereof being particularly preferred.

As examples of compounds of formula (g) may be given phenol, resorcinol, o- and p-cresol, o- and p-chlorophenol, 3-methoxyphenol and 3-hydroxyphenoxyacetic acid.

In the production of coupling components (fg), where mixtures of both compounds of formula (f) and compounds of formula (g) are employed, such mixtures preferably contain at least 50 mol %, more preferably at least 80 mol %, of the compound(s) of formula (f), it being still more preferable to employ solely the compound(s) of formula (f). In the most preferred embodiment, the reaction is carried out solely between salicylic acid and formaldehyde.

The mol ratio of formaldehyde to the compound(s) of formula (f) or (g) is preferably no greater than 0.95:1, the preferred mol ratio being the range of from 0.7 to 0.9:1.

If desired, the formaldehyde may be produced in situ, e.g. using paraformaldehyde, the amount of formaldehyde liberating agent being chosen, however, such that the required amount of formaldehyde is liberated. It is preferred, in fact, to work with paraformaldehyde.

The condensation is conveniently carried out in aqueous medium, in aqueous/inert organic medium or in inert organic medium, suitable organic media being formic and acetic acids. It is preferred, however, to work in aqueous medium. Elevated temperatures are generally employed, preferably from 50° to 130° C., more preferably temperatures close to the boiling point of the reaction medium, e.g. 90° to 130° C., and optionally under pressure. Mineral acids may be employed, as desired, to create the acid conditions for the reaction. However, where the compounds of formula (f) or (g) are employed in free acid form, the acidity thereof is generally sufficient. Where mixtures of compounds of formula (f) and/or (g) are employed and one component compound of the mixture is markedly more reactive than the other(s), such compound is preferably added slowly over the course of the condensation reaction, conveniently dissolved in an inert solvent.

The resulting product may be isolated in conventional manner.

The product of the condensation is a mixture of a broad spectrum of oligomerous condensates and is used as such, without separation of the various oligomers.

The preferred coupling components (fg) are those which are soluble to at least 10% in water at neutral pH.

Those products obtained from the reaction of salicylic acid, or its salts, and formaldehyde are preferred which have a Z value, where Z=I(CH₂)/I(aromatic), where I(CH₂) is intensity of the signal of methylene protons appearing between 3.0-4.3 ppm, and I(aromatic) is intensity of the signal of aromatic protons appearing between 6.3 and 8.2 ppm, (both measured by means of the NMR spectrum at 60 MHz in dimethyl sulphoxide/D₂ O) of from 0.43 to 0.85, more preferably from 0.5 to 0.7.

The course of the condensation can be followed chromatographically and the end of reaction ascertained by the loss of odour of formaldehyde from the reaction mixture when the formaldehyde is not employed in excess.

The preferred coupling component (fg) is (fg₁), i.e. the product of condensation, under acid conditions, of salicylic acid, or a salt thereof, and, optionally, resorcinol or a cresol, with formaldehyde, the mol ratio of formaldehyde to the other component(s) being from 0.6:1 to 0.95:1, preferably 0.7:1 to 0.9:1, at least 80 mol % of the other components being salicylic acid or a salt thereof.

The most preferred coupling component (fg) is (fg₂), i.e. (fg₁), above, but in which the formaldehyde is condensed with salicylic acid, or a salt thereof, alone.

Representative of the coupling components from which K₁ and K₂ are derived are K₁ "H and K₂ "H, i.e. compounds of the formulae ##STR13## in which Rp is hydrogen, OH,--NH₂, N(C₂ H₅)₂, --CH₃, --C₂ H₅ or unsubstituted phenylamino,

Rq is hydrogen, --CH₃ or --SO₃ M,

Rs is hydrogen or --CH₃,

Rt is --NH₂, --NHCOCH₃, unsubstituted phenylamino or --NH--CH₂ --SO₃ M,

Ru is --OH, --NH₂ or --NHCOCH₃,

Rw is --CH₃ or hydrogen, preferably hydrogen,

Rv is hydrogen, --CH₃ or --OCH₃, and

n is 1 or 2

and coupling components (fg₁), preferably (fg₂), as defined above.

Representative compounds of Formula I are those wherein each of K₁ and K₂ is the radical of a coupling component (fg), at least one of K₁ and K₂ being the radical of a coupling component (fg).

In the most preferred compounds provided by the invention, the radicals K₁ and K₂ are derived from coupling components K₁ '" and K₂ '", i.e. compounds (a₂₁), (a₂₂), (b₃), (c₃), (d₃), (e) and (fg₁), (fg₁) preferably being (fg₂), as defined below.

In general, but depending on the nature of the radicals K₁ and K₂, i.e. the number of aromatic nuclei contained therein and the presence or otherwise of carboxy groups, the compounds of formula I contain from 3 to 9, preferably at least 4 sulpho groups.

The invention also provides a process for the production of compounds of formula I, comprising

(a) coupling the diazo derivative of a diamine of formula II, ##STR14## with a coupling component K₁ H and a coupling component K₂ H, in any desired order,

(b) obtaining a compound of formula I, in which K₁ is free from diazotisable amino groups by coupling the diazo derivative of an amine of formula III, ##STR15## in which K₃ is the radical of a coupling component and is free from diazotisable amino groups, with a coupling component K₂ H, or

(c) obtaining a compound of formula I, in which K₂ is free from diazotisable amino groups, by coupling the diazo derivative of an amine of formula IV, ##STR16## in which K₄ is the radical of a coupling component and is free from a diazotisable amino group, with a coupling component K₁ H.

The above processes may be carried out in conventional manner, process (a) being particularly suitable for production of single compounds of formula I in which K₁ and K₂ are the same and for the production of mixtures of compounds in which K₁ and K₂ are different, processes (b) and (c) being particularly suitable for the production of single compounds in which K₁ and K₂ are different.

Coupling with a component (fg), (fg₁) or (fg₂) is carried out in a strongly alkaline aqueous or aqueous/organic medium, the pH preferably being at least 10, more preferably at least 12. Low temperatures, e.g. from -10° to 30° C., preferably 0° to room temperature, are employed. As examples or organic media can be given, for example, alcohols, tertiary aliphatic amines and amides.

Where a coupling component (fg₁) or (fg₂) is employed, there is a preferred ratio between the number of molecules of salicylic acid initially employed in the condensation reaction and the number of diazonium groups in the diazo derivatives compounds II to IV, such ratio being from 1 to 4:1, preferably 1 to 3:1.

The resulting compounds of formula I may be isolated and purified in conventional manner.

The compounds of formula II may be obtained by subjecting a compound of formula IX, ##STR17## in which Z₁ is --NO₂ or an acylamino group, and

Z₂ is --NH₂, --NO₂ or an acylamino group,

to reducing conditions when Z₁ and/or Z₂ is --NO₂ and/or to deacylation conditions when Z₁ and/or Z₂ is acylamino.

The compounds of formula IX may be obtained by coupling the diazo derivative of an amine of formula XI ##STR18## with a compound of formula XII, ##STR19##

The compounds of formulae III and IV may be obtained by subjecting, respectively, compounds of formulae V and VI, ##STR20## where Z is a nitro or acylamino group, ##STR21## to reducing conditions, when Z or Z₁ is nitro, or to deacylating conditions, when Z or Z₁ is acylamino.

The compounds of formulae V and VI may be obtained by coupling, respectively, to a coupling component K₃ -H or K₄ -H compounds of diazo derivatives of amines of formula VII or VIII, ##STR22##

The compounds of formula VII can be obtained from corresponding compounds in which instead of the terminal amino group there is a nitro or acylamino group by reduction or deacylation thereof, respectively, provided that when such group is nitro, Z is acylamino and when such group is acylamino, Z is nitro. The starting materials for such process and the compounds of formula VIII fall, of course, under formula IX.

The compounds of formulae XI and XII are either known or may be obtained from available starting materials in manner analogous to that for the known compounds.

The above reactions are carried out in conventional manner, e.g. reduction of nitro groups to amino groups by employing sodium sulphide as reducing agent and deacylation of acylamino groups to amino groups by employing basic conditions. The preferred acyl groups are the formyl and acetyl groups, particularly the latter.

The compounds of formulae II, III, IV and VI also form part of the present invention.

The compounds of formulae III, IV, VI and, especially, I are useful as anionic dyestuffs for dyeing substrates, whether textile or non-textile, dyeable using anionic dyes. Particular substrates are natural and regenerated cellulose, natural and synthetic polyamide, polyurethane, basic modified polypropylene, anodised aluminum and leather. Textile substrates may be in such forms as fibres, threads, filaments, non-wovens, felts, carpets, knitted, woven and finished goods. As examples of the natural fibre materials may be given cotton, wool and silk and of the synthetic fibre materials may be given nylon and basically modified polypropylene. Of particular interest is the use of the dyes, particularly the compounds of formula I, for the dyeing of cotton, cellulose non-woven fabrics, paper and leather, especially leather. The dyes may be applied in conventional manner, depending on the nature of the substrate to be dyed, e.g. using exhaust, pad-dyeing and printing techniques, in conventional amounts, e.g. up to the saturation level of the substrate. The dyeings obtained, depending on the particular dye employed, are dark blue, dark green or deep black and have satisfactory fastness properties. The dyes themselves are well soluble in water, show good resistance to acid and, especially on paper and leather, have relatively high substantivity, and give good penetration dyeings with leather.

The dyes may be employed as such or in dye preparation form, optionally in admixture with other dyes.

The following Examples, in which all parts and percentages are by weight and the temperatures are in degrees centigrade, illustrate the invention.

EXAMPLE 1 ##STR23##

138 parts of p-nitroaniline are diazotised in the usual manner with hydrochloric acid and sodium nitrite and are coupled at a pH of 1-3 with 319 parts of 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid. The diazo compound derived from 400 parts of 4-amino-4'-nitrostilbene-2,2'-disulphonic acid is coupled at a pH of 9.5 with the monoazo compound obtained above. The dinitrodisazo compound thus obtained is reduced in the reaction mixture at 40° with a solution of 234 parts of sodium sulphide in water. The dyestuff is separated by sprinkling in common salt and adjusting the pH to 1.5. The dyestuff obtained is mixed with dilute hydrochloric acid and is tetrazotised by adding dropwise 140 parts of sodium nitrite solution. 216 parts of 1,3-diaminobenzene, dissolved in water, are added to the tetrazotised dyestuff, and they are coupled at a pH of 5-10. The dyestuff obtained is precipitated with acid. It is a dark powder which dyes leather, paper, natural and synthetic polyamides and cotton in deep black shades.

If 2-chloro-4-nitroaniline or 2-sulpho-4-nitroaniline is used instead of p-nitroaniline, black dyestuffs with similar properties are obtained. If 1-amino-3-hydroxybenzene or 3-hydroxy-2'-methyldiphenylamine is used instead of 1,3-diaminobenzene, a black dye with similar properties is obtained. If 1,3-diamino-4-sulphobenzene is used instead of 1,3-diaminobenzene, an easily soluble dyestuff is obtained with the same properties.

Example X (production of coupling component (fg))

276 Parts of salicylic acid, 100 parts of 20% sodium hydroxide solution and 42 parts of paraformaldehyde are boiled at reflux for 10 hours. The resulting viscous melt, which no longer smells of formaldehyde, is dissolved with 2000 parts of 3% sodium hydroxide solution. 300 Parts of 30% hydrochloric acid are added quickly at 25° with good stirring. The condensation product in the form of a white precipitate is filtered off by suction, washed three times with water, dried at 100° in a vacuum and then ground to a powder.

Yield: 280 parts of a white powder with an acid equivalent weight of 160.

In the following Table 1 is given the structure of these and further dyestuffs which may be produced similarly to that of Example 1 and in the form of the free acid correspond to formula I, wherein the X's, A₁ and C₁ are sulpho, B₁ is hydrogen and Y, K₁ and K₂ have the definitions given in the corresponding columns, and M signifies hydrogen. Y being in meta-position to the K₂ -azo group.

                  TABLE 1                                                          ______________________________________                                                                             Shade of                                                                       dyeing                                     Ex.                                 on                                         No.  Y        K.sub.1 = K.sub.2     leather                                    ______________________________________                                         2    H                                                                                        ##STR24##            black                                        3  H                                                                                        ##STR25##             "                                           4  H                                                                                        ##STR26##             "                                           5  H                                                                                        ##STR27##             "                                           6  H                                                                                        ##STR28##             "                                           7  H                                                                                        ##STR29##            blue                                         8  H                                                                                        ##STR30##             "                                           9  H                                                                                        ##STR31##            green                                        10 H                                                                                        ##STR32##            blue                                         11 H                                                                                        ##STR33##             "                                           12 H                                                                                        ##STR34##             "                                           13 H                                                                                        ##STR35##             "                                           14 H                                                                                        ##STR36##            blue                                         15 H                                                                                        ##STR37##             "                                           16 H                                                                                        ##STR38##             "                                           17 H                                                                                        ##STR39##             "                                           18 H                                                                                        ##STR40##            dark green                                   19 H                                                                                        ##STR41##            green                                        20 H                                                                                        ##STR42##             "                                           21 H                                                                                        ##STR43##             "                                           22 H                                                                                        ##STR44##            dark green                                   23 H                                                                                        ##STR45##            dark green                                   24 H                                                                                        ##STR46##            dark green                                   25 H                                                                                        ##STR47##            green                                        26 H                                                                                        ##STR48##             "                                           27 H                                                                                        ##STR49##             "                                           28 H                                                                                        ##STR50##             "                                           29 H        Product of Example X, above,                                                                          "                                                       used in an amount corres-                                                      ponding to 1 molecule of                                                       salicylic acid originally                                                      condensed per diazonium group.                                     30 H                                                                                        ##STR51##            black                                        31 SO.sub.3 H                                                                               ##STR52##             "                                           32 SO.sub.3 H                                                                               ##STR53##             "                                           33 SO.sub.3 H                                                                               ##STR54##            blue                                         34 SO.sub.3 H                                                                               ##STR55##             "                                           35 SO.sub.3 H                                                                               ##STR56##             "                                           36 SO.sub.3 H                                                                               ##STR57##            green                                        37 SO.sub.3 H                                                                               ##STR58##             "                                           38 Cl                                                                                       ##STR59##            black                                        39 Cl                                                                                       ##STR60##            blue                                         40 SO.sub.3 H                                                                              "                      "                                           41 Cl                                                                                       ##STR61##            black                                        42 Cl                                                                                       ##STR62##             "                                           43 Cl                                                                                       ##STR63##            blue                                         44 Cl                                                                                       ##STR64##             "                                           45 Cl                                                                                       ##STR65##             "                                           46 Cl                                                                                       ##STR66##             "                                           47 Cl                                                                                       ##STR67##            green                                        48 Cl                                                                                       ##STR68##             "                                           49 Cl                                                                                       ##STR69##             "                                           50 Cl       Same as in Example 29 dark                                                                           green                                        51 OCH.sub.3                                                                                ##STR70##            black                                        52 OCH.sub.3                                                                                ##STR71##             "                                           53 OCH.sub.3                                                                                ##STR72##             "                                           54 OCH.sub.3                                                                                ##STR73##            blue                                         55 OCH.sub. 3                                                                               ##STR74##             "                                           56 OCH.sub.3                                                                                ##STR75##             "                                           57 OCH.sub.3                                                                                ##STR76##             "                                           58 OCH.sub.3                                                                                ##STR77##             "                                           59 OCH.sub.3                                                                                ##STR78##            green                                        60 OCH.sub.3                                                                                ##STR79##             "                                           61 OCH.sub.3                                                                                ##STR80##             "                                           62 OCH.sub.3                                                                               same as Example 29    dark                                                                           green                                        63 OCH.sub.3                                                                                ##STR81##            black                                        64 H        Product of Example X, above,                                                                         dark                                                     used in an amount corresponding                                                                      green                                                    to 1 molecule of salicylic                                                     acid originally condensed per                                                  diazonium group.                                                 65   Cl       Product of Example X, above,                                                                         dark                                                     used in an amount corresponding                                                                      green                                                    to 1 molecule of salicylic                                                     acid originally condensed per                                                  diazonium group.                                                 66   OCH.sub.3                                                                               Product of Example X, above,                                                                         dark                                                     used in an amount corresponding                                                                      green                                                    to 1 molecule of salicylic                                                     acid originally condensed per                                                  diazonium group.                                                 67   SO.sub.3 H                                                                              Product of Example X, above,                                                                         dark                                                     used in an amount corresponding                                                                      green                                                    to 1 molecule of salicylic                                                     acid originally condensed per                                                  diazonium group.                                                 ______________________________________                                    

EXAMPLE 68 ##STR82##

138 parts of p-nitroaniline are diazotised in the usual manner with hydrochloric acid and sodium nitrite and are coupled at a pH of 1-3 with 319 parts of 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid. The tetrazo compound consisting of 370 parts of 4,4'-diaminostilbene-2,2'-disulphonic acid is coupled on one side at a pH of 5-10 with the monoazo compound obtained as above. After coupling, 199 parts of 3-hydroxy-2'-methyldiphenylamine, dissolved in water, and caustic soda are added to the diazodisazo compound thus obtained and coupling is brought to an end at a pH of 10. The nitrotrisazo compound obtained is reduced in the reaction mixture at 40° with a solution of 117 parts of sodium sulphide in water. The dyestuff is separated by sprinkling in common salt and adjusting the pH to 1.5. The dyestuff thus obtained is mixed with dilute hydrochloric acid and is diazotised by adding in drops 70 parts of sodium nitrite solution. 199 parts of 3-hydroxy-2'-methyldiphenylamine, dissolved in water, and caustic soda are added to the diazotised dyestuff and are coupled at a pH of 10.

The dyestuff thus obtained is precipitated with acid. It is a black powder which dyes leather, paper, natural or synthetic polyamides or cotton in deep black shades.

If 2-chloro-4-nitroaniline, 2-sulpho-4-nitroaniline or 2-methoxy-4-nitroaniline is used instead of p-nitroaniline, black dyestuffs with equally good properties are obtained.

In the following Table 2 is given the structure of further dyestuffs which may be produced similarly to that of Example 68 and which in the form of the free acid correspond to formula I wherein the X's, A₁ and C₁ are sulpho, B₁ is hydrogen and Y and K₁ K₂ have the definitions given in the corresponding columns and M signifies hydrogen.

                                      TABLE 2                                      __________________________________________________________________________                                              Shade of                              Ex.                                      dyeing on                             No. Y  K.sub.1         K.sub.2           leather                               __________________________________________________________________________     69  H                                                                                  ##STR83##                                                                                      ##STR84##        black                                   70                                                                               H  "                                                                                               ##STR85##        "                                       71                                                                               H  "                                                                                               ##STR86##        "                                       72                                                                               H  "                                                                                               ##STR87##        "                                       73                                                                               H  "                                                                                               ##STR88##        "                                       74                                                                               H  "                                                                                               ##STR89##        "                                       75                                                                               H  "                                                                                               ##STR90##        "                                       76                                                                               H  "                                                                                               ##STR91##        "                                       77                                                                               H  "                                                                                               ##STR92##        blue-black                              78                                                                               H  "                                                                                               ##STR93##        "                                       79                                                                               H  "                                                                                               ##STR94##        "                                       80                                                                               H  "                                                                                               ##STR95##        "                                       81                                                                               H  "                                                                                               ##STR96##        "                                       82                                                                               H                                                                                  ##STR97##                                                                                      ##STR98##        green                                   83                                                                               H  "                                                                                               ##STR99##        "                                       84                                                                               H  "                                                                                               ##STR100##       "                                       85                                                                               H  "                                                                                               ##STR101##       "                                       86                                                                               H  "                                                                                               ##STR102##       "                                       87                                                                               H                                                                                  ##STR103##                                                                                     ##STR104##       green                                   88                                                                               H  "               same as Example 29                                                                               "                                       89                                                                               H  "                                                                                               ##STR105##       black                                   90                                                                               H  "                                                                                               ##STR106##       "                                       91                                                                               H  "                                                                                               ##STR107##       "                                       92                                                                               H  "                                                                                               ##STR108##       "                                       93                                                                               H  "                                                                                               ##STR109##       "                                       94                                                                               H  "                                                                                               ##STR110##       "                                       95                                                                               H  "                                                                                               ##STR111##       "                                       96                                                                               H  "               same as Example 29                                                                               "                                       97                                                                               H                                                                                  ##STR112##                                                                                     ##STR113##       black                                   98                                                                               H  "                                                                                               ##STR114##       "                                       99                                                                               H  "                                                                                               ##STR115##       dark green                              100                                                                              H  "                                                                                               ##STR116##       "                                       101                                                                              H                                                                                  ##STR117##                                                                                     ##STR118##       green                                   102                                                                              H  "                                                                                               ##STR119##       "                                       103                                                                              H  "                                                                                               ##STR120##       "                                       104                                                                              H  "                                                                                               ##STR121##       "                                       105                                                                              H  "                                                                                               ##STR122##       green-black                             106                                                                              H                                                                                  ##STR123##                                                                                     ##STR124##       black                                   107                                                                              H  "                                                                                               ##STR125##       "                                       108                                                                              H  "                                                                                               ##STR126##       "                                       109                                                                              H  "                                                                                               ##STR127##       "                                       110                                                                              H  "                                                                                               ##STR128##       "                                     111 H                                                                                  ##STR129##                                                                                     ##STR130##       blue                                    112                                                                              H  "                                                                                               ##STR131##       "                                       113                                                                              H  "                                                                                               ##STR132##       "                                       114                                                                              H  "                                                                                               ##STR133##       blue-black                              115                                                                              H  "                                                                                               ##STR134##       "                                       116                                                                              H  "                                                                                               ##STR135##       black                                   117                                                                              H  "                                                                                               ##STR136##       "                                       118                                                                              H  "                                                                                               ##STR137##       "                                       119                                                                              H  "                                                                                               ##STR138##       "                                       120                                                                              H  same as Example 29                                                                              ##STR139##       green                                   121                                                                              H  "                                                                                               ##STR140##       "                                       122                                                                              H  "                                                                                               ##STR141##       "                                       123                                                                              H  "                                                                                               ##STR142##       "                                       124                                                                              H  same as Example 29                                                                              ##STR143##       "                                       125                                                                              H  "                                                                                               ##STR144##       black                                   126                                                                              H  "                                                                                               ##STR145##       "                                       127                                                                              H  "                                                                                               ##STR146##       "                                       128                                                                              H  "                                                                                               ##STR147##       "                                       129                                                                              H                                                                                  ##STR148##                                                                                     ##STR149##       "                                       130                                                                              H  "                                                                                               ##STR150##       "                                       131                                                                              H  "                                                                                               ##STR151##       "                                       132                                                                              H  "                                                                                               ##STR152##       "                                       133                                                                              H                                                                                  ##STR153##                                                                                     ##STR154##       blue-black                              134                                                                              H  "                                                                                               ##STR155##       blue                                    135                                                                              H  "                                                                                               ##STR156##       black                                   136                                                                              H                                                                                  ##STR157##                                                                                     ##STR158##       blue-black                              137                                                                              H  "                                                                                               ##STR159##       blue                                    138                                                                              H  "                                                                                               ##STR160##       black                                   139                                                                              H                                                                                  ##STR161##                                                                                     ##STR162##       blue-black                              140                                                                              H  "                                                                                               ##STR163##       blue                                    141                                                                              H  "                                                                                               ##STR164##       black                                   142                                                                              H                                                                                  ##STR165##                                                                                     ##STR166##       blue-black                              143                                                                              H  "                                                                                               ##STR167##       blue                                    144                                                                              H  "                                                                                               ##STR168##       black                                   145                                                                              H                                                                                  ##STR169##                                                                                     ##STR170##       blue-black                              146                                                                              H  "                                                                                               ##STR171##       blue                                    147                                                                              H  "                                                                                               ##STR172##       black                                   148                                                                              H                                                                                  ##STR173##                                                                                     ##STR174##       blue-black                              149                                                                              H  "                                                                                               ##STR175##       blue                                    150                                                                              H  "                                                                                               ##STR176##       black                                   151                                                                              H                                                                                  ##STR177##                                                                                     ##STR178##       blue-black                              152                                                                              H  "                                                                                               ##STR179##       blue                                    153                                                                              H  "                                                                                               ##STR180##       black                                   154                                                                              H                                                                                  ##STR181##                                                                                     ##STR182##       blue-black                              155                                                                              H  "                                                                                               ##STR183##       blue                                    156                                                                              H  "                                                                                               ##STR184##       black                                   157                                                                              H                                                                                  ##STR185##                                                                                     ##STR186##       blue-black                              158                                                                              H  "                                                                                               ##STR187##       blue                                    159                                                                              H  "                                                                                               ##STR188##       black                                 __________________________________________________________________________

DYEING EXAMPLE A

100 parts of newly tanned and neutralised chromium grain leather are milled for 30 minutes in the dye tub in a liquor consisting of 250 parts of water at 55° and 1 part of the dyestuff of Example 1. The leather is treated for a further 30 minutes in the same bath with 2 parts of an anionic fat-liquor based on sulphonated train oil, and it is then dried and curried in the usual manner. A very evenly dyed black leather is obtained.

DYEING EXAMPLE B

100 parts of calf suede are milled for 4 hours in the dye tub with 1000 parts of water and 2 parts of ammonia and subsequently dyed in a new bath. 500 parts of water at 55°, 2 parts of ammonia, 10 parts of the dissolved dyestuff of Example 1 are dyed for 11/2 hours in the dye tub together with the calf leather which has already been milled. In order to exhaust the dyebath, 4 parts of formic acid (85%) are slowly added, and dyeing continues until the dyestuff has been fixed completely. The suede leather which is rinsed, dried and curried in the normal manner is a very evenly dyed, deep black suede, after buffing the suede side.

DYEING EXAMPLE C

100 parts of lamb's leather, chromium-vegetable tanned, and 10 parts of the dyestuff of Example I are milled for 45 minutes in the dye tub in a liquor consisting of 1000 parts of water at 55° and 1.5 parts of an anionic emulsion of spermaceti oil, and the dyestuff is fixed on the leather by slowly adding 5 parts of formic acid (85%) for 30 minutes. After the usual drying and currying processes, a leather is obtained in a very even deep black shade.

DYEING EXAMPLE D

A solution of 20 parts of the dyestuff of Example I in 847 parts of water, 150 parts of ethylene glycol and 3 parts of formic acid (85%) is applied by spraying, plushing and coating to the grain side of a buffed, compound-tanned cow hide. The leather is dried and curried under mild conditions. A leather is obtained in a deep black shade, with very good fastness properties.

DYEING EXAMPLE E

260 ml of water at 50°-60° are placed in a 500 ml dye beaker which is located in a heatable water bath, and 10 ml of 10% sodium sulphate solution, as well as 1 ml of 10% sodium carbonate solution are added. 0.25 g of the dyestuff of Example I are made into a good paste with 2 ml of cold water, and 30 ml of warm water (50°-60°) are added; the dyestuff then dissolves. The dye solution is added to the prepared bath and 10 g of cotton fabric are kept in constant movement in this dyebath. The temperature of the dyebath is increased over the course of 30 minutes to 85°-90° and dyeing continues at this temperature for 60 minutes. The dyed material is removed from the dyebath, the adhering liquor is removed by wringing out, and the material is rinsed for 5-10 minutes in cold water and dried at 60°-70°.

DYEING EXAMPLE F PAPER

(a) 100 parts of chemically bleached sulphite cellulose (of conifer or hard-wood) are ground in a hollander in 2000 parts of water. 4 parts of the dyestuff of Example I are added to this pulp as a powder or in solution. After 15 minutes, sizing takes place, and subsequently fixation. Paper produced from this pulp has a deep black dyeing with good fastness to the wet and to light.

(b) 70 parts of chemically bleached sulphite cellulose (of conifer wood) and 30 parts of chemically bleached sulphite cellulose (of birchwood) are beaten in a pulper in 2000 parts of water. 0.4 parts of the dyestuff of Example I are sprinkled into this pulp or are added as a solution. Paper is produced from the pulp after 20 minutes. The paper produced from this pulp is dyed grey and has good colour fastness.

By replacing the dyestuff of Example 1 in the above Examples A-F by the corresponding amount of one of the dyestuffs from examples 2 to 159, further dyeings are obtained.

In the above dyeing examples, the dyestuffs are used in blended form with sodium carbonate. 

What is claimed is:
 1. A compound of the formula ##STR189## wherein each of A₁, B₁ and C₁ is independently hydrogen or --SO₃ M, with the proviso that when A₁ is --SO₃ M, one of B₁ and C₁ is --SO₃ M and the other is hydrogen and when A₁ is hydrogen, B₁ is --SO₃ M and C₁ is hydrogen, each of K₁ and K₂ is independently the radical of a coupling component of the formula ##STR190## or the radical of a coupling component (fg), said coupling component (fg) being the product of the condensation, under acid conditions, of formaldehyde and (a) a compound of the formula ##STR191## or a mixture of such compounds, (b) a compound of the formula ##STR192## or a mixture of such compounds, or (c) a mixture of at least one compound of the formula ##STR193## and at least one compound of the formula ##STR194## with the provisos that the mol ratio of formaldehyde to the other compound(s) is at least 0.5:1 and that at least 50 mol % of the other compound(s) contain a --COOM group, whereinR₁ is hydroxy, --NH₂, C₁₋₄ alkylamino, di-(C₁₋₄ alkyl)amino, C₂₋₄ hydroxyalkylamino, di-(C₂₋₄ hydroxyalkyl)amino, N-C₁₋₄ alkyl-N-C₂₋₄ hydroxyalkylamino, --NHCH₂ SO₃ M, arylamino, N-C₁₋₄ alkyl-N-arylamino or N-C₂₋₄ hydroxyalkyl-N-arylamino, wherein any aryl is phenyl; naphthyl; substituted phenyl having 1 to 3 substituents each of which is independently C₁₋₄ alkyl, C₁₋₄ alkoxy (not more than two), nitro (not more than two), chloro (not more than two), --COOM (not more than one) or --SO₃ M (not more than one); or naphthyl substituted by 1 or 2 --SO₃ M groups, with the proviso that the hydroxy group of any C₂₋₄ hydroxyalkyl moiety is not on the α-carbon atom, R₂ is hydrogen, hydroxy, --NH₂, C₁₋₄ alkyl, C₁₋₄ alkoxy, chloro or acylamino, R₃ is hydrogen, C₁₋₄ alkyl, --SO₃ M or --COOM, R₄ is hydroxy, --NH₂, phenylamino or (substituted phenyl)amino wherein substituted phenyl has 1 to 3 substituents each of which is independently C₁₋₄ alkyl or C₁₋₄ alkoxy (not more than two), R₅ is hydrogen, hydroxy, --NH₂, --NHCH₂ SO₃ M or acylamino, R₆ is hydrogen, C₁₋₄ alkoxy or --COOM, with the proviso that R₆ must be hydrogen or C₁₋₄ alkoxy when m is 2 or 3, R₇ is acyl, R₈ is phenyl; naphthyl; substituted phenyl having 1 to 3 substituents each of which is independently C₁₋₄ alkyl, C₁₋₄ alkoxy (not more than two), chloro (not more than two), acetyl (not more than one) or --SO₃ M (not more than one); or naphthyl substituted by 1 or 2 --SO₃ M groups, each of R₁₃, R₁₄, R₁₅ and R₁₆ is independently hydrogen; fluoro; chloro; bromo; iodo; hydroxy; C₁₋₄ alkyl; C₁₋₄ alkyl substituted by fluoro, chloro, bromo, iodo, --COOM, cyano, hydroxy, C₁₋₄ alkoxy or C₁₋₄ hydroxyalkoxy; C₁₋₄ alkoxy or C₁₋₄ alkoxy substituted by fluoro, chloro, bromo, iodo, --COOM, cyano, hydroxy, C₁₋₄ alkoxy or C₁₋₄ hydroxyalkoxy, and m is 1, 2 or 3, wherein each acyl and acyl moiety of acylamino is independently phenylsulfonyl, tolylsulfonyl, benzoyl, (C₁₋₄ alkyl)carbonyl or acetoacetyl, with the proviso that at least one of K₁ and K₂ is the radical of a coupling component (fg), each X is hydrogen or --SO₃ M, with the proviso that the two X's are the same, Y is hydrogen, C₁₋₄ alkyl, C₁₋₄ alkoxy, hydroxy, fluoro, chloro, bromo, --COOM or --SO₃ M, and each M is hydrogen or a non-chromophoric cation.
 2. A compound according to claim 1 wherein each M is hydrogen, an alkali metal cation, an alkaline earth metal cation or .sup.⊕ N(R)₄, wherein each R is independently hydrogen, C₁₋₃ alkyl or C₂₋₃ hydroxyalkyl, with the provisos that when at least one R is C₂₋₃ hydroxyalkyl, at least one R is hydrogen and the hydroxy group of each C₂₋₃.spsb.- hydroxyalkyl is not on the α-carbon atom.
 3. A compound according to claim 2 wherein each M is hydrogen, lithium, sodium, potassium or .sup.⊕ N(R)₄.
 4. A compound according to claim 1 wherein each of R₁₃, R₁₄ and R₁₆ is independently hydrogen, methyl, methoxy, hydroxy or chloro, and R₁₅ is hydrogen, methyl, methoxy, hydroxy, chloro or --O--CH₂ --COOM.
 5. A compound according to claim 4 wherein each of K₁ and K₂ is the radical of a coupling component (fg), K₁ and K₂ being identical.
 6. A compound according to claim 5 wherein at least one of R₁₃ and R₁₄ is hydrogen.
 7. A compound according to claim 6 wherein each of R₁₃, R₁₄ and R₁₅ is hydrogen, and R₁₆ is methyl or m-hydroxy.
 8. A compound according to claim 7 wherein each of K₁ and K₂ is the radical of a coupling component (fg₁), said coupling component (fg₁) being the product of the condensation, under acid conditions, of formaldehyde with (a) salicylic acid, or a salt thereof, or (b) a mixture of salicylic acid, or a salt thereof, and resorcinol or a cresol, with the provisos that the mol ratio of formaldehyde to the other compound(s) is 0.6 to 0.95:1 and that at least 80 mol % of the other compound(s) is salicylic acid, or a salt thereof.
 9. A compound according to claim 8 wherein each of K₁ and K₂ is the radical of a coupling component (fg₂), said coupling component (fg₂) being the product of the condensation, under acid conditions, of formaldehyde with salicylic acid, or a salt thereof, with the proviso that the mol ratio of formaldehyde to the other compound is 0.6 to 0.95:1.
 10. A compound according to claim 9 with the proviso that the compound contains at least four --SO₃ M groups.
 11. A compound according to claim 1 with the proviso that the compound contains 3 to 8 --SO₃ M groups. 